Variable-speed gear



mch 11 1924. 1,486,7Mr

T. VICARS ET AL VARIABLE SPEED GEAR Patented Mar. it, 1224.

'KHQMAS VICARS AND EDWARD LYNTON VICARS, 0F EARLESTOWN, ENGLAND.

VARIABLE-SPEED GEAR.

Application filed July 7,

To all whom it may covwem:

Be it known that we, THoMAs VIOARB and EDWARD LYNTON VICARS, subjects ofthe King of England, and residing at Earlestown, in the county ofLancaster, England, have invented Improvements in Yarlable- Speed Gears,of which the followlng 1s a specification.

This invention has reference to varlable speed gears of the kind inwhich a belt consisting of a multiplicity of transverse bars or teeth onan endless band work in connection with two V pulleys each consisting oftwo relatively adjustable coned discs, mounted and movable on shafts, towhich they are operatively connected by means of splines extendingcompletely through the bosses and parts of the discs, the halves ofwhich discs are moved simultaneously towards and away from one another,respectively, by means of screw gear acting through double pivotedlevers, one in connection with each side of a pulley; so that, as thisscrew gear is operated, the two discs of each pulley operated u on, aremoved towards one another, an awa from one another, respectively. The safts, screw gear and parts are all carried in a suitable frame.

In this speed change gear, the splines or keys of the disc shafts, whichare carried completely through the bosses and parts of the discs, aremade long enough to give a full bearing of the parts in any positionupto the extreme outward positionof the coned discs and parts; and thebosses are made sufiiciently strong to allow the keyways to be outcompletely through, and a relatively large ball thrust bearing used. Thehousing of the thrust bearings of the disc shafts is kept in position bya plain collar which may be advantageously secured by two screws, halfin the boss and half in the collar.

By this means the necessity of the splines being kept short enough toclear the thrust housing, as in some cases at present, when the discsare at the closest position, is avoided, in which cases a very shortbearing on the splines exists, when the discs are at th widest positionapart; and even in the case where the thrust bearings are on the bossesof the discs, and the splines or keyways are not cut through the boss,only a short bearing of the splines is furnished 1921. Serial No.4.222%.

in the outermost positions of the discs, and this is avoided by thisinvention.

On the back of the coned discs, which slide on the supporting shafts,are V-shaped rojections or bosses, connected with thrust bearings whichthe inner edges of the double operating levers act on, the thrustbearing and its housing being between the levers and the discs and lyingwithin the double levers.

The invention is illustrated in the annexed drawings, in which Fig. 1 isa plan of the improved variable speed gear, and Fig. 2 is a sectionalview showing one of the cone shafts and thrust bearing.

Referring to the drawings, 1 are the cone discs,2the bosses or hubs ofsame,3 are their supporting shafts, 4 are the bearings of the shafts,and 5 the frame in which the bearings are mounted. 6 are the doubleoperating levers, pivoted at 7 to the transverse shafts 8 in the knownway. 9 is the operating threaded shaft having on its outer end theoperating chain wheel 10. 11 are the ball or roller thrust hearings onthe bosses of the discs 1, by which the thrust of the discs 1 is takenupon the V-shaped portions 12 of the housings of which, the edges of thelevers 6 bear and act; the housings being disposed within the doublelevers. The hubs 2 are formed to provide inner reduced portions 20terminating at the forward ends in shoulders 21. Mounted on thesereduced portions and abutting against the shoulders are ball thrustbearings 22. A bearing ring 23 encloses each thrust bearing, bears uponthe reduced portion 20, and against the outside member of each thrustbearing. Each bearing ring 23 is held in position by a collar 24 securedupon the reduced portion 20, the bearing rings being further formed withshoulders 25 for the operative engagement of the portions 12 of thehousings.

The keys or splines in the shafts 3 are marked 13, see more particularlyFigure 3, and are of such a length that when the discs 1 are moved apartfor their maximum position, the keys will still be within the wholelength of the keyways of the bosses 2 of the discs, so that the discsalways have a full bearing on the splines or keys in any position towhich they may be moved.

By this means, the discs are easily moved on the shafts 2, even if theyare kept running in one position for a long length of time; as b thisarrangement the splines or keys and eyways of the bosses do not becomeindented, which if they did, and do in some constructions heretoforeused, make it difiicult to move the discs, which is the object andeffect of this invention to obviate.

In this gear, the housings of the thrust bearings 11 are kept inposition by a plain collar 14 secured with two screws (not shown) halfin the boss and half in the collar.

What is claimed is In a variable speed gear, the combination of a frame,two parallel shafts mounted therein, a spline on each shaft extendingsubstantially the full length of the same, a pair of cone-shaped drivingelements held on said shaft by the spline and adapted to slide towardand away from each other, a reduced portion on the outer end of thebearing of each driving element to provide a shoulder, a ball thrustbearing mounted thereon, V-shaped elements associated with said ballthrust bearing, levers pivoted between the parallel shafts and havingtheir relatively inner edge portions engaging the said- V-shapedelements, said levers being otherwise free of connection with thedriving elements, and means cooperating with the levers for operatingthe same to cause said levers to exert endwise pressure on the V-shapedelements of one pair of driving elements while freeing pressure on theV- shaped elements of the other pair of driving elements.

In testimony whereof we have signed our names to this specification inthe presence of two subscribing witnesses.

THOMAS VI-CABS. EDWARD LYNTON VICARS.

Witnesses:

GWEN EDWARDS, EUNICE A. Enwanns.

